Projectile adapter



' c a. H. JAKoBssoN PRoJEcTILE ADAPTER Fiied June 3,'1941 adapter will soon be again.. n

'against thevforward end Ofi the' extension is preferably eased ,by supplyingy la. buffer or brake atl tachment. for the barrel. extension' l In'the accompanyinggdrawingg,oneemhodment lof-.fthe .invention is illustrated. and l Patented Aug. 14, 1945 "Gustav: Herman; Jakobsson,

v assigner, of 'one-third tov .Einreise` f washinennrnc.

. ff Application lunes, 1

:retoma Park.. :Maig- H.' Purdy. l

941.,.seriamntasi4sa i claims. (ci. 1oz-f9.3) t

' The-present invention relates lto^afdevice for making it; possible to fire a projectilelfrom a gun of `larger caliber'in-orderito considerably increase its`4 range and Without anyVv change oftheflarger gun. In this vmanner'a.nd-loy2giving"thesarne muzzle energy to the small projectile asl isordi-` narilyused for the projectileof the-largery gun, the range of thefformer will be increased several times withoutany extra cost.

Inorderto carry out this invention anl adapter in the shape of a cradle is used and whichihas an outside diameter that ts the bore of thevlarger gun'and a recess or pocket suitableto `house the smallprojectile, sayl 2.1.5 pounder 'or-f0.7 kg.,` 3'7 mm.,A in for instance a 'lv-51mm. antilaircraft gun and-by using the regular Acharge of the latter, the f muzzle energy oi the -37 mm; shell and adapter, weighing together( about 2.5 pounds 1.12 kg. ywould be increased to vabout foot-tons, which should at leasty triple its range.l Upon 'ring the gun thissmall `projec'rtile andl cradl'e will leave the gun'bore together, but on account of its larger cross-sectional area at :the-ratio-of about 4 to. vl, givinga higher air resistance, the lefty behindV and the shell alone proceed at an increased ratel of velocity.

If thensetto explode at an-altitude of say sixmiles it-would illuminate any'l objects vin itsneighbourhood, thus disclosing yto vthe gunners on the ground the whereabouts of Y enemy planes to be fired'at. As no searchlight then needs tn be used, the position ci?I the anti-aircraftgun would not be disclosed tothe enemy. a considerable advantage. v n

This arrangement wouldV be best" suited ffor guns on board ship, as- Ithe` adapters when free wouldfallbeyond the railing ofv` the ship and drop into the water. But in order to collect the fired adaptersand more particularly to protect the gun crew when firingfon land, a 'barrel extension is attached' tothe gun 'muzzle so as to 'separate the adapter' from theV projectile and permitfit to fall down in a -basketfor-a-t' a, predetermined place on the ground, thusto bereloaded and used The force of impact ofA the adapter Eile.. .,.1 is an axial' eet,l r.1.v ci therradle Withithe shell? in, position and'. .1e-cartridge casefattechedto .the .rearend: off .the cradlaready '.forl loading: .in `a. gunofzlarger. caliberthansaid 1Shelli;

vilaljasticl materiali may. also. be

Fig. y2 yis afliwlfvcrossesectionion: line; 2;-2; of Fig- 172' x'. f

f l lig; Sais 'afhalf rcarrend view andahalf.: cross sectionionlineee-l of'fE-lg..1;. 1. f I. r Fig. Aaltop'rplan view voithc.- cradle, partly in section.; l* 1'.:

Fig. 5 a rear-encl'vievvv oftheshellri l,

Fig; 6 an axialzse'cticm .off-a' muzzle. attachment forcatching the cradle upon :leavingrthcbore of thelgun artersring.; @-1

li'ig.v 8 is: a cross section-...on linef-'ffof Eig. 6 lookinaltuwards the-fronti'.` f" i On the drawing the adapterforscradleeislfdef noted in generali. by; numeral i in',- vIt; consists: of a1 base for: rearzidislc.. LI.;y one'. .diameter suitable to fit.` :the: bore .nl shown; in; dos: and:l dash. lines.V in Fig; l of' a.. gunfiori instance. a antieaircraft gunfromiwlhicha smaller projectile: infthis examplefa 3ft isintendedzto hev fired.. Naturally: `other sizesfof gunsy andi/'shells may bey se lectedfas for'examplearl mm. gunziorfa '75. shell'fand sd-fo'm'th. .Y -1

f.. 1. i Aroundlfthe 'adapterxbase lilzzis crimped ordove.- tailedf in -the-.usualmannenia vriidingfhandz.I4 similarrtofthat used on; 15 mm ammunition in theexample,-l und'er discussion,l` 'forjithe .purpose of? engaging the. riding :and giving. the. rotation, rst'.; te 'ther adapter endif then.,coxnrnunicated vto -the'projectil'e carried therein. and? numbered.' i3 oni the drawing.. Thesdisk: H- forms Y a' solid .base

'againstY whichvthazpowder chargeenclosed inthe cartridge caseiil' is exploded; the llatter'gripping thefrear-enct-oiltheihasez.ll-tightly; y p

'The adapter ismadeof vlight material in order to.. keep the; combined. weight of projectile and adapten lowV as possible, in this instance- 2.5 pounds-.jor a' Llxpound', 370mm; shell with a one poundadapter.: `I).uralurninor any similar alloy would vhe suitable, butt fireproof'i or `nonfflreproof used;- In the latter case-.aimcta-l platez ifimay/ beeprovided in` the bottom; of :the-.irecess: or annular space' l1 formed in' theendot thti disk: lvl. Thiswspace aswell as the space i8 on the forward side ofthe dislnl Il is provided fior; they sake 'of lightness: 'Iihe-'front portion of the adapterv cons-ists offfai. similar disk t9: whichwgis saucer yshaped having. an annular depression, Non its forward .side partly forilight- .ness `and i also.. in orden to collect fthe-meeting yair in flight. A tubular middle portion Zisconneets a unitary constnucticnoiithe adapten. ''he'itubular.: portionit'mayebcperforated: as at nftotmake itiflzhter. Lt: continues to' theizforward side l 'of the disk I9 to form a rim 23 around the shell. The inside diameter of this tubular portion and rim is slightly more than that of the shell so as to permit the shell to slip out easily from Ithe cradle after ring. A seat or recess 25 for the shell is provided in the disk II having the same diameter as that of the tubular portion 2 I.

suitablemeans forkeying thel shell...l 3. to the adapter III is provided maycdsistof inter-v engaging lands and grooves at the end of the shell and in the bottom of the seat 25 as shown at 26 I or along the side face near the edge of the shell.

In the bottom of the seat 25 is showna'"d'epres-Y L sion forming a chamber 2'I` intended toholdl a small powder charge which'lifs'tilmeld to ,explode when the adapter leaves the'bor'e of the'gun in order to assure the separation of the adapter from the shell, so as to send the latter'forward.alone,

which dropping the adapter behind more, quiclfb,A ly than by the air pressure alone. This may be ac'" complishedl in .any suitable l manner, as for. instance by a slow burning pellet in the passage 50,' which'connects the .disk Vrecess IJ and th'e chamber 21 containing said `small .powderlcharge,'jsee Fig,A .1; i Upon ringthe gun', the regular .powder charge, contained in the cartridge case :I 5,.'will thus ignite the'pellet in thepassage 5IJ.' 5

. Therforward'rim 23 is providedlwithla number of longitudinal passages orslots `28 with radial vents 29 for permitting compressed air, collecting in the-.saucer 'shaped depression 205m th'e front disk I9to.1low in' a stream against the side of the shell and thus further aid the shell to slip easilyoutoftheadapter -r Y l :In Figs. 6:7 and.`8*isshownadevice forposi-A tively arresting the ight of. the adapters directly after leavingV the muzzlefofthe gun, so th'at they may be collected. for use again. This would make afurther saving in the` use of this invention. f :In Fig., 6, the muzzle end of thegun isdenoted by numeral 35 and `shown at an elevationlof 30?., .but generallyV a much higher elevation woulclzbe used. Back of the bourrelet 35a.of,the 'muzzle-is -secured the lrear end ofthe `barrel extension` 31, which extension has .the .general shape of ahollow, truncated4 cone; terminating in front wit-ha head38 which ris reinforced tobe abletowithe standlthe impacts of theadapters IU during firing. `The head 38 haslacentral apertureyof slightly larger diameter. than the shell I3 :which h'as -to pass thru unobstructed. ..Within the hollowporftion of the'vhead 38 is lodgecla resilient. member 40, consisting for instanceof a coiledspring with a washer 4| behind it for. contacting with the ad'- -yancing .adapter IIIv to A.stop it in its course and throw it outthru the .opening formed between the arms 42, twoor more in number and which constitute the middle. portion of the barrelexvtension'fl. The rear end vthereof is'made in as many ring-sections. as there are arms 42 and form the ends of the latter. 'I'li'isfpez-'mits of .their spreading topass over the bourrelet of the gun muzzle in order to be secured onthe gun by means of a clamping band 43 orbyf any other suitable means.

Instead of making the barrel extensioninone piece it may be made telescopic and todraw the `head 4backtowards the gun muzzle bymeans of 4a spring or; the like.` Theuhead would then yield keying device at 26 to the shell I3, which latter will be sent forward spinning and with considerably increased velocity and passing thru the aperture 39, while the adapter will, on the other hand be stopped in its flight and thrown to the ground or collected in a receptacle for further use,

It will be evident that the invention is not limited 'to the details ol,` construction here shown and described, but that these may be, varied widely without departing fromthe spirit of th'e invention as dened by the claims.

""Another and equally important advantage of 'this' invention resides in the use of the adapter :for firing ammunition of odd calibers from larger guns in which itdoes not fit. When for instance anfarmy'succeeds in driving enemy troops from a invention may therefore at times; be the cause of winning a battle, if shortage of ammunition were experienced, when now enemy shellscan be immediatelyused, Y 1 -.I=claim: Y I

. 1. In an adapter for ringva projectile from a gunof larger Caliberand with a correspondingly increased charge, comprising a cradle having a diameter fitting the bore of said gun and an axial seat adapted to house said projectile, a rifling band around the cradle suitable for said gun bore andfmeans for -positively keying the projectile in ,the oradle circumferentially while permitting easy axialseparation,v whereby Vthe twistof the riing -will-be communicated to said projectile to produce thedesired rotation during flight, affront disk and afrear disk atra suitableldistanceapart and a Mtubular *connecting portion'between said disks, each offthe disks having an annular, forward facing depression forming an air pocket with vents ,from said depression towards the face ofthe projectile for ,the purpose of` facilitating the separavtion of cradle and projectile,

2,'In'anfadapterrforring a projectile `from a gun'of larger caliberI and with a correspondingly .increasedcharge,comprising a cradle having a diameter tting the bore of said gun and an axial seat adapted to .house said projectile, a rifling Aband around the cradle suitable for said gun bore 4and means for positively keying th'eprojectile in the cradle. circumferentially while permitting easyl axial separation, whereby the twist of the .riing will.V be communicated Vto said projectile `toproduce thedesired rotation during flight, a front diskand a rear disk at a suitable distance apart anda .tubular connecting portion between .said disks, eachof the disks Ahaving an annular, forward facing depression forming an air pocket with vents from the depression towards the face 'of the` projectile, 'a' central chamber formed in the seat 'of the rear disk adapted to carry a powder :charge for the Vpurposepf facilitating the separaupon impact ofthe adapter against v.it `to lessen 7,0 tion ofcradle and projectile.;

theblowx.- U.

Upon ring th'e adapter;carrying the shell, .the latter will be givena rotation,xco1responding to thetwist of the` riing.as-communicatedlfrom 3. vIn an adapter for ringa projectile from a lgunaof larger 'caliber and with a correspondingly Aincreased. charge, comprising a cradle having a .diameter iitting thelbore of said gunand an axial seat adapted to house. said projectile, variiiing band around the cradle suitable for said gun bore and means for positively keying the projectile in the cradle clrcumferentially while permitting easy axial separation, whereby the twist of the rifling will be communicated to said projectile to produce th'e desired rotation during flight, in which said cradle comprises a front disk and a rear disk at a suitable distance apart and a tubular connecting portion between them, said keying means being axially slidable and comprises ribs in the cradle-seat adapted for engaging corresponding groove formed in the projectile; said disks having a greater transverse area than that of the inserted projectile providing a considerably greater air resistance during flight, thus aiding in separating said projectile from the cradle.

4. Inan adapter for firing a projectile from a gun of larger caliber and with a correspondingly increased charge, comprising a cradle having a diameter tting the bore of said gun and an axial seat adapted to house said projectile, a rifling band around the cradle suitable for said gun bore and means for positively keying the projectile in the cradle circumferentially while permitting easy axial separation, whereby the twist of the rifling will be communicated to said projectile to produce the desired rotation during flight, in which said cradle comprises a front disk and a rear disk at a suitable distance apart and a tubular connecting portion between said disks, said keying being adapted for circumferential locking but permitting axial sliding between the projectile and the cradle, said disks having a greater transverse area than that ofthe inserted projectile whereby th'e inequality against air resistance will aid in separating the adapter from the projectile during ight.

GUSTAV HERMAN J AKOBSS'ON. 

